A substantial industry exists for the production of high purity sodium hydroxide (NaOH) and chlorine gas from the electrolysis of brine (sodium chloride solution). The production of NaOH via the electrolysis of brine is presented in equation I below:NaCl+H2O→½H2(g)+½Cl2(g)+NaOH  (I)As shown, brine electrolysis also results in the production of hydrogen and chlorine gas as byproducts. Traditionally such byproducts have been disposed of by combustion to produce HCl and heat, neither of which appears to have much value in the production of NaOH. The combustion of these byproducts to produce HCl is outlined in equation (2) below, in which ΔG is the change in Gibbs free energy.½H2(g)+½Cl2(g)→HCl(g) ΔG=−133 kJ/mol  (II)
As can be seen from equation (II), the reaction proceeds spontaneously to form HCl. It is also exothermic and so may require significant cooling water to control temperature. Moreover, while combustion may facilitate disposal of the byproducts produced by brine electrolysis, it does little to offset the energy cost of the process. With this in mind, some research has aimed to develop fuel cells that utilize hydrogen gas as a fuel, chlorine gas as the oxidant (hereinafter, H2—Cl2 fuel cells), and hydrochloric acid as an electrolyte. Although such research has demonstrated that H2—Cl2 fuel cells show promise for generating electricity that may offset the energy cost of the brine electrolysis process, such fuel cells may suffer from various problems that may complicate or prevent their practical application in this and other industries.